↵a OR for autism associated with a 1 U increase in exposure. For prenatal exposure, 1 U = 1 μg of ethylmercury. For postnatal exposure, 1 U = 1 μg of ethylmercury per 1 kg of body weight at time of vaccine or immunoglobulin receipt.

↵b OR for autism associated with an increase in exposure equal to 2 SD units of the exposure measure. For the measure of prenatal exposure, 2 SDs = 16.34 μg. Two SDs of the birth-to-1-month measure is 4.08 μg/kg U. Similarly, 2 SDs of birth-to-7-month and birth-to-20-month exposures are 15.56 μg/kg and 17.82 μg/kg.